On Tuesday, Haleh Esfandiari, director of the Middle East Program at the Woodrow Wilson International Center for Scholars in Washington, was put behind the bars of Tehran's notorious Evin prison. Esfandiari, a respected scholar of dual Iranian-American citizenship, had been detained last December by Iranian authorities and barred from leaving the country.

Over the last four months, the scholar, who taught Persian language and literature at Princeton for 14 years until 1994, was subjected to long interrogations on an almost daily basis but allowed to return each evening to the home of her 93-year-old mother, whom she had traveled to Iran to visit. On Tuesday Esfandiari was again summoned by Iran's intelligence ministry - but this time taken to prison, where she has remained since.

Esfandiari's arrest is but the latest chapter in a crackdown on intellectuals and writers in Iran over the last year. Last spring Iran arrested the philosopher Ramin Jahanbegloo and kept him behind bars for four months, floating vague accusations of "contacts with foreigners" and extracting a confession from him, though never formally charging him. Similarly, no charges have yet been brought against Esfandiari.

The Committee on Academic Freedom of the Middle East Studies Association of North America (MESA) has condemned Iran's imprisonment of Esfandiari, as has Human Rights Watch, which fears that the 67-year-old scholar may have been subjected to coercive interrogation. The human rights group also points out that Esfandiari's arrest took place during a particularly onerous week in Iran, one that saw "escalated repressive campaigns against Iranian women's right activists and student leaders".

But it isn't just the last week. In a climate that the writer Praful Bidwal aptly describes as having grown "palpably more unfree, tense, apprehensive and insecure" in the last year, the government of Mahmoud Ahmadinejad has announced a purge of liberal and secular professors from Iran's universities, harassed and banned several student organisations, shut down scores of newspapers and magazines and clamped down on the country's women's rights movement, which has been gaining momentum in recent months.

Another possible reason for her arrest is alluded to in a Wilson Center statement, which says that the questioning to which Esfandiari has been subjected has "focused almost entirely on the activities and programs of the Middle East Program at the Wilson Center. Repeatedly during the interrogation, Dr Esfandiari was pressured to make a false confession or to falsely implicate the Wilson Center in activities in which it had no part."

The US State Department has made $75m available for "democracy promotion" in Iran, and Tehran clearly believes that the center is involved in such activities. But the center's president and director, former Congressman Lee Hamilton, insisted in a letter to Ahmadinejad that his group has received no state department money. Indeed the Washington Post's Robin Wright, author of The Last Great Revolution: Turmoil and Transformation in Iran, describes the Wilson Center as "one of the few places in Washington to offer a robust range of opinions on Iran." (Hamilton also co-chaired the Iraq Study Group, which emphatically urged the Bush administration to engage Iran.)

Yet Washington's announcement of the democracy-promotion provision has functioned as a noose around the neck of Iranian civil society--this despite the fact that no activists or intellectuals in the country want a penny of it. As the Iranian dissident Akbar Ganji argues, those funds only "make the work of the pro-democracy movement more difficult. The government of Iran describes all of its opponents as agents of the United States [and] claims they are on the payroll of the Bush administration."

And that's precisely what's happened to Esfandiari. Although no formal charges have been brought against her, the Tehran-based newspaper Kayhan, a mouthpiece for the Islamic Republic, has accused the scholar of spying on behalf of the US and Israel and of attempting to foment a democratic revolution in Iran.

The notion that Haleh Esfandiari, who is known for her political independence, would be an agent or on the take of any government is laughable to those familiar with her and her work. In a letter to Iran's authorities calling for her immediate release, the Committee for Academic and Intellectual Freedom of the International Society for Iranian Studies (of which I am co-coordinator) describes Esfandiari as a "staunch advocate of pursuing peaceful dialogue between Tehran and Washington in resolving their diplomatic standoff".

Indeed, as Karim Sadjadpour of the Carnegie Endowment for International Peace told the Washington Post, the irony is that in Washington, Esfandiari has "faced criticism for bringing in people who were sympathetic" to the Iranian government. "By detaining her," Sadjadpour noted, "the Iranian government only eliminates an advocate for diplomacy and strengthens the voices of those in Washington who say the regime is cruel and should not be engaged."

Maybe that's precisely the point.

At a moment when signs seemed to be pointing toward a diplomatic thaw between Washington and Tehran, hardliners in both capitals have been maneuvering to avert that scenario. A calming of tensions - not to speak of a restoration of diplomatic relations between the two countries - Nasrin Alavi has argued, "would reduce state domination of an economy (supported by huge oil reserves) that is crippled by corruption and negligence, and loosen the control of social and political life by state institutions such as the Revolutionary Guards and their allies": a sequence of events, that is, from which the Ahmadinejad wing (precisely the Revolutionary Guards and their allies) stand to lose a great deal.

Thus just as the US hawks have thrown a lifeline, as Ali Ansari has observed, to an increasingly unpopular and embattled Ahmadinejad, the phenomenon appears to be rather a two-way street. By locking up someone like Esfandiari "on bogus charges and continuing a nasty domestic crackdown," a recent Los Angeles Times editorial astutely argued, "the Iranian president not only looks like a paranoiac increasingly prone to dangerous miscalculation, he plays into the hands of US hawks eager for a confrontation."

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